Screw press



Aug. 28, 1951 Filed 001:. 6, 1950 F. BURGHAUSER SCREW PRESS 3 Sheets-Sheet 1 INVENTOR.

. Franz Burghauser H/S ATTORNEYS Aug. 28, 1951 F. BURGHAUSER SCREW PRESS 3 Sheets-Sheet 2 Filed 001;. 6, 1950 INVENTOR. Franz Burghauser BY HIS ATTORNE Y5 Aug. 28, 1951 F. BURGHAUSER SCREW PRESS 3 Sheets-Sheet 5 Filed Oct. 6, 1950 vOOOOOOOOOOOAOOO OOOO OOA INVENTOR. Franz Burghauser H/S ATTORNEYS Patented Aug. 28, 1951 UNITED STATES PATENT OFFIG-E 52,565,947 "'"sci'mw Passe l Franz Burghauser, Bayern,;Ge1-many w Application-center c, iasaseriai No; 188,701

This inventionrelates to improvements in ma- -chines oi the screw orworiii type'suchjas are used to squeeze, grind or otherwise, treat a food or other material under pressure in-ordertoextract a liquid therefrom, or crushthem'aterial, or for any other purpose. g

j Conventional press machines comprisea stator or housing in which a rotor in the form of ascrew or worm is rotatably carried, the housing'and rotor cooperating'to form a generally helic'alwork passage throughwhich the material moves in passingthroughthe press. ,The Wall'ofthe'hous- -ingat the :passage is provided with materialholding grooves or tracking elements; and the rotor usually comprises 'a screw having a thread ofhelical-design having-a significant pitch,"1ead or-advance at substantially all its points, but

with 'the pitoh, f1ead'or'advance decreasing in a direction along the'work passageleading to its discharge. 'The'grooves hold thefmaterial against free rotation with the screw; and the decreasin I advance-of the threadbuilds u a pressure on the material-inthe "work passage. The screw may Qb'e-piovided withinorethan one thread, especialiy near the dischargeend of the 'wo'rk passage. The efiicien-cy of such' press' machinesis usually comparatively low, a drawback being the tendency of material to flow back"when*sizeab1e pressures are-builtfup.

' object of i the present invention isto provide a press-"machine of the type-described'that "iacks the foregoing disadvantages, butwhic'h, instead, can produce relatively higherfpressures on the material} passing therethr ough. Accordingly; a press machine embodying myinvention is much more 'efiective and eificient "for-squeezing,

feeding, grinding, crushing or otherwise treating 'ma' terialsfed therethrough -'as compared to prior machines of comparable size.

Another object-of my invention" is to"pro'vide a press inaohine' having'a' work passage that 'eX- tends from the feed end -to the disehargeendpf the press, but has one onmore-annularstages therealong -with substantially no pitch or ad== Vance. v v

A further'obje'ctof my invention is to provide 'apress' machine comprising-a cylinder or hens-- in'g and'a'rotor that cooperateto -iorm the worl: passage; but" one of these elements having a threadwith one or a plurality of" thread=turns,

each of which is slightly l'ess -than a' complete "circle and has no pitch or advance, the? threadturns having joining'or interconnecting threadportionsthat doi-hav'e a'sig'nificant pitch-or: angle of advance. The spaces betweenithread turns tiiorm channels-which 'also= have'noadvanee andv 55 "a're'part of the work-passage.... Byano advance I mean having no progressing component in the axial" direction of the thread so. that the channelsare circular in planes perpendicular to 5 the axis. Each channel cooperates Lwithaasimilax-groove onthe other elementto form aniannular treatment stage in the press.

- 'Afurther Object of my inventionistmprovide an'iinprovedpress machine of theitypenescribed 10 having a plurality of annulanstagesiwhich:are

spaced along the axis of the press xbuttare interconnected by short channel portions. having desired pitcher advance. A further object of my inventionis'totprovide an -improvedpress machine of-the type r described ar; treating highly compressible -materia1;.-1.the press"liaving a plurality of pressure stages;:.each successive stage being zvolumetrically smaller tlia'n the preceding. stage BOEGCOIIIIHOCIELB the V decreased volume of the material. beingntreated.

' ;A further object of my inventioni islto provide press machine'of the type describedihaving a =Worm comprising a central shaft -or -stem land a5 relatively wide' -thread along the': stem;.. IIhe g5 "s-tem' an'dthread zare -hollow, with the .latter "vide=a pressfmachine of thejtype" descrih ed in which the thread is onjan finternalwall o ;the stationary housing orgylinder of press li Other features; objectives, and "accomplish- ,m'ents of my invention, in; addition to "the rare- .t going, Will be discernible from thefollowing de- ..seription ,of} preferred formsjthereof tgfthe specific details of, which the. broad aspects 1 enee a v y-net li i v, de cr .ti0n: is to be taken in- Qonjunctionggwi-th .the ac- '3 companyin drawings, in which:

Fig; 1 is: an axial ,SBCtiOlJ-Gl-iViEW-Offl (press machine embodying the principles .offmys invention;

Fig; 2 is atsectionalx.viewsimilar;toiFig;;11,;but iwith the worm .omitted; 'and;takeni-substantially i'on'thelineIIz-lI of Fig.3;

Fig. 3 is a sectional view taken substantially on the line III-III of Fig. 1;

Fig. 4 is an axial sectional view of a modified press machine embodying my invention, useful for extracting or expressing juice, oil, or other liquid from the material under treatment;

Fig. 5 is an axial sectional view of another modified press machine embodying my inven-* tion, the machine having a mincing means for reducing a material to a fine iorm prior to entering the worm;

Figs. 6 and 7 are sectional views taken substantially on the lines VI-VI and VII-VII of Figs. 4 and 5, respectively;

Fig. 8 is an axial sectional View of still another modified press machine embodying my invention, the machine having the arrangement of the grooves and channels on the housing and rotor reversed as compared to the arrangement of the grooves and channels of the embodiments shown in Figs. 1-7; p V

Fig. 9 is a planar develcpmentof the inner wall surface of the housing of Fig. 8 for illustrating the channel construction on the housing; and

Fig. 10 is a sectional view taken substantially on the line X-X of Fig. 8.

In general, an embodiment of my invention, as shown in Figs. 1-3, comprises a press machine which is indicated by a cylinder or housin 2 and a rotor consisting of a rotatable worm 4. The housing 2 has a feed-in chamber 6 and a cylindrical wall [0 having an axis co-axial with that of the worm 4. V

The worm .4 comprises an axially extending central portion or stem l2 integral with an outer thread or flight H. The worm is rotatably mounted in the housing 2. To this end, the stem l2 has a projecting shaft portion l6 journalled in a boss I! in a wall of the housing 2. The other end of the worm 4 comprises a round disc l8 that closely rotatably fits the adjacent portion of the inner surfaceof the wall Ill. A turning torque, either a manual or power drive, is applied to the shaft portion l6 for turnin the warm 4 in the housing 2. p The thread [4 of the worm 4 has a conventional helical portion [9 in the feed-in chamber 6 that feeds the raw material to a, work passage in the press. The work passage is formed by the thread i 4 and the inner surface of the wall I. h

In accordance with my invention, the work passage comprises a plurality of annular stages, each of which has no continuous axial advance. The stages are spaced along the axis of the housing 2, and each stage comprises a pair of grooves or channels, one of which is provided in the housing wall of the pressmachine and the other of which is provided by the rotor. Adjacent stages are interconnected by a short helical 0r advancing channel portion provided on the thread.

With reference to Figs. 1-3, the inner surface of the housing wall ID has a plurality of grooves, three bein shown in the embodiment being described and identified by the reference numerals 2D, 22' and 24: These grooves are separated from each other and other openings in the press walls by wall portions 26, 28, 30 and 32, in the form of complete bands or ridges. Each of the ridges has a smooth, circularly round inner face or surface of noticeable width. Preferably, each of the grooves vill, 22 and 24 has a tubular face that is provided7with numerous small zig-zag teeth 34 around itsi'periphery, as indicated in Fig. 3.

, The portion of the thread I4 that is withinthehousing wall it] comprises a plurality of spaced 4 turn portions providing as many channels in the worm as there are grooves in the housing wall. Accordingly, the worm 4 has spaced channels 36, 38 and 40 separated by thread-turns 42, 44, 46 and 48; the thread-turn 48 corresponding, in this embodiment, to the outer circumferential portion of the end disc I8. In a sense, the threadturns are ridges on the stem 12 of the worm.

The housing 2 carries the worm 4 so that the grooves 20, 22 and 24 in the housing are kept radially aligned with the channels 36, 38 and 40, respectively, in the worm. Accordingly, the

, groove 26 and the channel 36 form a first stage,

the groove 22 and channel 38 a second stage, and the groove 24and channel 40 a third stage for the work passage in the press machine. The widths of the intervening housing ridges and threadturns should be adequate to keep the stages separated for any axial play that the worm may have in the housing. The thread and ridges can be made comparatively thick.

The material to be treated is fed to the different stages in succession by having the thread-turns, with the possible exception of the last threadturn, less than a complete circle, that is, less than 360 angular degrees, so that each thread-turn has a circumferential open portion, and displacing the open portions of the thread-turns in an angular direction in which the worm turns during operation Accordingly, in passing from one thread-turn to the other, the interconnecting thread portion is helical or advances axially along the worm. Referring specifically to Fig. l, the feed-in thread portion IQ of the worm merges into the leading end of the first thread-turn 42. An interconnecting helical thread portion connects the lagging end of the thread-turn 42 to the leading end of the second thread-turn 44, and a helical thread portion 52 similarly connects the thread-turns 44 and 46. As is better shown in Fig. l in connection with the thread portion 52, each thread portion has a width that fully spans the associated stage, so that the only communication between adjacent stages is through a single channel portion defined by open portions of the thread-turns, associated threadturns and helical thread portions. The tips of the teeth 34 are along the circumference in which the outer edge of the associated interconnecting thread portion rotates, forming a seal therewith, as better shown in Fig. 3. By confining the communication between each pair of successive stages substantially to a single opening or channel portion, high pressures can readily be built up at the discharge end of the press machine and without significant flow-back of material.

In operation of the press machine, the worm 4 turns in the direction of the arrows 54, and the housing ridges 26, 28, 3G and 32 can be said to provide bearings for the thread-turns 42, 44, 4B and 48. Raw material is fed into the feed-in chamber 6. The helical thread portion I9 in this chamber forces the material through the interconnecting channel at the open part of the first thread-turn 42, and into the first annular stage formed by the housing groove 20 and the Worm channel 36. The material then passes from each stage to the next in a similar manner, moving through the work passage in a plurality of alternating circular paths and short helical paths until it is discharged into a pressure line through any suitable discharge opening 58 which, in this embodiment, leads from the groove 24 in the housing wall Ill.

The embodiment of my invention shown in Figs. 4 and 6 is constructed along the same general lines as that of Figs. 1-3. The press machine of Figs. 4 and 6 comprises a housing 62 and a worm 54. The housing 62 has a feed-in chamber 66 and a cylindrical housing wall 68 having an inner surface provided with alternating housing grooves and ridges, the grooves having teeth, such as 35 of Fig. 3, and the last groove having a discharge opening I2.

The housing further comprisesan end closure 14 at the discharge end having a chamber 16 into which the discharge opening I2 opens. The end closure 14 has an outlet 18 controlled by-apressure-regulating valve 89in the form ofan-adjustable screw.

The worm G4 has astem with a shaft portion 84 at its end which is j ournalled in the end clo= sure Hi. This shaft portion 84 and the portion'of the stem which parallels the housingwall' 68 are hollow so as to provide an axial liquid-outlet passage 86 for juice or oil extracted from the material fed to the press. The extracted liquid reaches this passage 86 through a plurality of radial openings or holes 88 in each of the threadturns of the worm, theholesextending'from the passage 85 to the periphery of the thread-turns.

Liquid squeezed from the material flows into the clearancespaces between the thread-turns and housing ridges to the holes 88. This liquid flows inwardly through the 'holes and into the axial passage 86. The remaining solid substance of the material moves through the work passage in the press, reaching the chamber I6 and passing out of the press through thepressure-regulating valve 80.

Attention is called to Fig. 6 as more clearly showing a circumferential opening 92 in a thread-turn, the open arc subtending approximately 80 angular degrees so that the threadturn embraces more than three quadrants.

Liquid can be extracted from some materials, such as, for example, potatoes, carrots, beets and some fruits, more efiiciently if the material is first cut up or otherwise minced before reaching the treatment stages of the press. In accordance with this aspect of my invention, a means for accomplishing such mincing is added to the feedin chamber of the press. This means comprises two cooperating elements, the first of which is fixed to the housingand the second to the rotor or worm. Figs. and '7 illustrate a modification of this kind, adapted to a press of the type shown in Figs. 4. and 6.

The press machine of Figs. 5' and 7 comprises a feed-in chamber 94 comprising an offset wall 96, and a deepened bottom wall 98. The press machine also comprises a hollow cylindrical hous ing wall E05 fitted to the chamber 94 and having a wall portion I02 thatextends into the chamber. The wall portio'n"l02 is open at the top, in line with the feed-in opening of the chamber 94; and the leading face I04 of the wall portion I02 is beveled to a fine edge.

The press machine also comprises a worm I05 having an end plate I08 fixed thereto which carries a perforated tubular member I ID that passes around the outside of the fixed wall portion I512. The tubular member IIU is in the form of a shredder or cutter having a plurality of small raised cutting portions at its numerous openings, such as is found in grating or shredding boards known in the art. As the shredder or cutter I I0 rotates with the worm, it minces the raw material fed to the chamber 94, the cut up material passing through the numerous openings in the receives thecut up or mashed material and drives it forwardly for pressure treatment within the housing I as of the press. -It is-also possible to pass the material from one stage tothe'next via interconnecting channel portions in the stationary housing wall rather "than in the rotating worm, as described in connection with-the prior embodiments. For such construction,theoutside of the worm has the equivalent of-the circular grooves such as 20-, 22 and 24 of Fig. 1; and the inside of the housing is provided with an internal thread that has spaced thread-turns having no pitch or lead; the thread= turns being interconnected by shorter thread p'ortionsthat do; The press machine shown in gigs. 8, 9 and 10 includes this and other modificzw ons.

The press machine of Figs. 8-10 comprises a stationary housing comprising a hollow clon gated housing wallIZO having a feed-in chamber I22. The machine also comprises a rotor I24. rotatably carried in the housing and comprising a feeder portionj'lzt that rotates in the feed-in chamber I22 and a material-holding portion I23v that rotates in'thefhousing wall I253.

The press housing has an end wall I23 in which an end of therotor ms is journalled. An internal thread I30 in the-housing may be said to begin at the peripheral portion of this wall E29.

- and to extend along the inside of the housing wall I20 to the discharge end thereof. As will be apparent from fFig. 9, the thread I36 starts with a short axially advancing thread portion tion I36, a less than360 degree nonadvancing thread-turn I38,"a shortadvancing threadportion I40, a less than 360 degree nonadvancing. "thread-turn I'4'2,"a short advancing thread portion Hi l, a less than 360 degree thread-turn HIS,

a short" advancing thread portion Hi8, and-so on, 'dependingonthe number of stages in the press, 'until the threadmakes a complete circular turn iiilat the end of the housing wall I20. Accordingly, the inside of the housing has a plurality ofyspaced nonadvancing channels I52, I55. I56, I-58-and' Hid-interconnected by short advancing channel portions 5'62, I64, I68 and I68.

It is to be noted that in this particular embodiment, the successive axially sloped thread portions I32, I36,;I4ll, t le and Id? are progressively shorter in a direction from the feed end of the machine to-the discharge end. The various nonadvancing channels are also progressively smaller in width in the same direction so as to accommodate the progressively decreased mass of a compressible material feeding through the press machine. It is also to be noted that the circumferential openings in the nonadvancing thread-turns are also progressively smaller in accordance with the size of the channels so that the interconnecting channel portions are of correspondingly less width. For further accommodating the lesser volume of the material as it is progressively compressed or treated, the channels can also be made of decreasing heights in the axial direction of flow of the material,

as clearly shown in Fig. 8. The compressed material leaves the machine through a discharge I10 at the lagging end of the last channel I50.

The rotor I24 is provided with a plurality of completely circular ridges I12, I14, I16, I18 and I80 spaced along the outside of the rotor so as to be directly radially opposite the thread-turns I34, I38, I42, I45 and I50, respectively, of the internal thread I30 of the press housing. The spaced rotor ridges separate completely annular grooves I02, I09, I95, I88 and I90 on the outside of the rotor. Each of the last four of these grooves corresponds in width to that of the holising channel which it faces and forms therewith an annular stage of the press, in the same mannor as dESCllI')d in connection with Figs. 1-7.

The outer periphery of each of the grooves is formed with saw-like teeth, such as indicated by the reference numeral I92 in Fig. 10, which correspond to the teeth 34 of the previously described embodiments. The teeth I92 help to advance the material through the work passage of the press.

For liquid extraction, each of the thread-turns in the housing Wall I29 is provided with a multiplicity of radially outwardly extending holes I94.

The work passage formed by the cooperating stationary housing element and the rotor element of Figs. 8-10 is'continuousfrom the feed end of the press to the discharge end of the press, and can be said to wind around the axis of the rotor element. As with the other embodiments, the work passage comprises a plurality of axially spaced annular stages or passage portions which have no axial advance or lead, the stages being generally circular in planes perpendicular to the axis of the rotor. The various stages are interconnected by slanting or helical channel portions or passage portions that have an axial advance,'and the material under treatment is forced from one stage to the next along one of these passage portions. The saw-like teeth in the various stages help to keep the material in the stages moving in the proper direction in the Work passage, and form a barrier or seal for confining communication between adjacent stages to the axially slanting passage portions. It is also to be noted that in the embodiment shown in Figs. 8-10, the volume of the respective stages decreases in the direction in which the material flows through the press. A similar expedient can obviously be applied to prior embodiments.

While I have described certain presently preferred embodiments of my invention it is to be understood that it may be otherwise embodied within the scope of the appended claims.

I claim:

1. A worm-type press of a type described comprising a worm thread comprising an advancing feed-in thread portion followed by a pluralityof alternating non-advancing thread-turns and adsaid non-advancing thread-turns, and teeth between said ridges, said member and worm thread being relatively rotatable.

2. A worm-type press of a type described comprising a rotor member and a cylindrical member surrounding said rotor, one of said members having thereon a worm thread comprising an advancing feed-in thread portion followed by a plurality of alternating non-advancing threadturns and advancing thread portions joining said thread-turns, providing circumferential openings in said thread-turns, the other of said members having thereon a plurality of spaced circular ridges forming grooves therebetween of substantially the width of said non-advancing thread-turns and being radially in line with said non-advancing thread-turns, and teeth between said ridges, said members being relatively rotatable.

3. A press machine as defined in claim 2 characterized by said thread being an internal thread on said cylindrical member, and said ridges being on the outside of said rotor member.

FRANZ BURGHAUSER.

REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS Number Name Date Re.21,449 McNitt May 14, 1940 625,394 Hook May 23, 1899 741,898 Fahrenholz Oct. 20, 1903 797,374 Roberts Aug. 15, 1905 842,236 Neukirchen Jan. 29, 1907 938,766 Hubert Nov. 2, 1909 1,069,404 Fiddyment Aug. 5, 1913 1,219,279 Fiddyment Mar. 13, 1917 1,338,120 Brundage Apr. 27,1920 1,514,279 Fiddyment Nov. 4, 1924 1,782,368 Vandergrift June 10, 1930 1,769,658 Veenhuyzen July 1, 1930 2,149,736 Hiller et a1 Mar. 7, 1939 2,319,859 Hale May 25, 1943 2,496,625 Henning Feb. 7, 1950 2,510,429 Ross June 6, 1950 FOREIGN PATENTS Number Country Date 104,151 Switzerland Apr. 1, 1924 6,436 Netherlands 1 Dec. 15, 1921 443,481 Great Britain Feb. 28, 1936 452,161

Great Britain Aug. 18, 1936 

